As known in the art to which the present invention pertains (hereinafter, ‘the related art’), reductive amination is one of methods for obtaining an aliphatic alkane derivative to which amine groups are introduced through a catalytic amination-reaction of the aliphatic alkane derivative under a reductive condition and in the presence of hydrogen. Such reductive amination has been used for preparing various amine compounds such as polyetheramine.
The polyetheramine compound is a compound having at least one polyoxyalkylene group, and it is being used in various ways such as a coating agent for wind power generators, an additive for epoxy coating, an additive for concrete, and the like, and it is generally prepared through reductive amination-reaction by using a compound such as a polyalkylene glycol and the like as a starting material.
In such reductive amination-reaction, a copper (Cu)-nickel (Ni) based catalyst is generally used, and there has been many attempts to increase productivity by controlling the catalytic activity by using chromium (Cr), titanium (Ti), zirconium (Zr), zinc (Zn), molybdenum (Mo), and the like as an active component.
However, the reductive amination-reaction is accompanied by the processes of dehydrogenation, dehydration, and hydrogenation, and the existing catalysts disclosed above have a problem that they lose activity easily by moisture formed during the reductive amination-reaction, or a side-reaction proceeds by the excessive moisture, and the reaction efficiency finally decreases.
To make up for this problem, a method of eliminating moisture formed during the reaction from the reaction system by carrying out the reductive amination-reaction in a continuous process has been used. However, this continuous process has a disadvantage of that complex facilities are needed and overall production efficiency decreases.
Therefore, the development of new catalyst which has a balance of dehydrogenation and hydrogenation reactions and can maintain the catalytic activity even in a batch-type process for preparing a polyetheramine compound is urgently needed.